The use of bolt operated automatic and semi-automatic rifles is widespread and in all military and law-enforcement environments. Under normal operating conditions, a user can manually retract the bolt carrier group of such rifles by pulling back on the charging handle in order to load the rifle or to clear stoppages. However, certain malfunctions require the user to retract the bolt carrier group with additional force beyond what is necessary for normal operation. Unfortunately, there are neither any features integral to the M16 system nor are there any aftermarket solutions that allow for additional mechanical advantage to be applied in such circumstances. Standard techniques for clearing such a malfunction require the user to remove the rifle from the shoulder and strike the butt of the rifle against a firm surface while simultaneously hitting, unlocking and retracting the charging handle. This technique requires physical dexterity and greatly reduces the tactical awareness of the user.
Additionally, the use of sound suppression devices was apparently not heavily considered during the development of the M16 system. These devices increase the duration of the pressure spike of combustion gasses and often times force excess gas around the charging handle and directly into the face of the user. There is currently an aftermarket replacement part (the GAS BUSTER by Precision Reflex Inc.) that mitigates this problem for a right-handed user. However, this design does not allow for additional mechanical leverage and directs some gas through the right-hand side of the rifle towards a left-handed operator's eyes and face.
Finally, there are reports of the charging handle failing under extreme usage. Although the exact nature of these failures is not specified, it is most likely that these failures occur when the charging handle is in the extended position and then subjected to excessive lateral or upward forces. This could bend the charging handle enough to prevent the bolt carrier group from closing. In this scenario, the rifle becomes completely inoperable until the charging handle can be removed, replaced or possibly bent back into place (which may cause a full breakage). In this case, it is possible for the rifle to function without a charging handle but the rifle's usability and operational abilities become extremely hindered.
What is required, therefore, is a new replacement assembly or assemblies that will integrate mechanical advantage bolt retraction and gas-blowback diversion to the M16 Rifle Series. Additionally, the new assembly should seamlessly integrate into the M16/M4 platform, function ergonomically and safely, be unobtrusive, not impair the user in any way and operate in all military and law-enforcement environments. Specifically, such a replacement assembly should be able to increase the speed and ease of clearing jams such as a stuck case, stuck bolt, live round double-feed, empty case double-feed (i.e. ejection failure), certain failures to extract, and even case head separation, possibly with the assistance of a broken shell removal device in this later scenario.